KUALA LUMPUR, Malaysia – Police abuse is a serious human rights problem in Malaysia, with unjustified shootings, mistreatment and deaths in custody occurring in large part because the police lack accountability, Human Rights Watch said Wednesday.

The group's report came as the Malaysian police force is being scrutinized over its investigation into the pilots and crew on the missing Malaysian jet.

The 102-page report was based on interviews with 75 people in Malaysia including victims of police abuse and their family members, lawyers, police officials including the current chief and human rights activists. It documented scores of suspicious shootings and incidences of alleged torture by officers.

"This is about a police force that is unaccountable and in some cases out of control," said Phil Robertson, the group's Asia director, at a briefing in Kuala Lumpur. "The Malaysian police needs to put in place effective oversight of the police to end the wrongful deaths, preventable abuse in custody and excessive use of force on the street."

Police and home ministry officials were not immediately available for comment.

Human Rights Watch urged the government to create an independent commission with powers to investigate allegations against the police.

Earlier Wednesday, Police Inspector General Khalid Abu Bakar told reporters that investigation into the pilots and crew of the missing jetliner could take a long time, and he warned that it might not result in any answers to what occurred on the plane, which went missing on March 8 with 239 people on board.

He said that all the passengers had been cleared of anything suspicious in relation to the plane's disappearance.

Malaysia is one of the most developed countries in Asia and prides itself on being a democracy.

But the media is mostly state-linked and rarely criticizes the government, and there are increasing concerns over freedom of religion. The government is campaigning against Shia Islam, which it regards as heretical, and has forbidden Christians to refer to God as "Allah," a ban that is seen as pandering to hard-line Muslims.